Tim Birkhead
Author of ‘The Wisdom of Birds‘
Tim Birkhead is a professor of behaviour and evolution at the University of Sheffield. His research on promiscuity and sperm competition in birds helped to re-shape current understanding of bird mating systems. His undergraduate teaching (for which he has two awards) includes courses in animal behaviour and the history and philosophy of science. He hates administration.
Tim's research has taken him to Canadian High Arctic, Labrador, California, Australia, Africa and Europe. Since 1972 he has maintained a long-term study of guillemots on Skomer Island, Wales which is where he did his PhD. Tim has been president of the International Society for Behavioural Ecology and currently serves on the management committee of the Darwin Correspondence Project. Tim initiated the biennial Biology of Spermatozoa (BoS) meetings at Losehill Hall, Derbyshire in 1992. He was elected a Fellow of the Royal Society in 2004.
As well as a passion for research, Tim is committed to undergraduate teaching and the public understanding of science and. He has given talks to non-scientists at book festivals, the Royal Institution, at Café Scientifique and elsewhere. He has written for New Scientist, BBC Wildlife, Natural History magazine and the Independent and has a regular column in the Times Higher Education. He has written or edited 10 books, including Promiscuity (2000 Faber & Faber). His popular science books have gained widespread recognition and The Cambridge Encyclopaedia of Ornithology was awarded the McColvin medal for best reference book (1991), and The Red Canary (Weidenfeld & Nicolson 2003) was awarded the Consul Cremer Prize. His most recent book The Wisdom of Birds is an illustrated account of how we know what we know about birds.
He is married and has three (recently fledged) children and a dog, enjoys walking, playing guitar and painting in his spare time.
About this talk
Birds, a perennial human fascination, entertained medieval homes long before science took them for serious study. "Wisdom of Birds" author Tim Birkhead tours some intriguing birdwatcher lore (dug up in old field journals) -- and talks about the role it plays in ornithology today.
Friday, October 01, 2010
TALKS - Julian Treasure: Shh! Sound health in 8 steps
About this talk
Julian Treasure says our increasingly noisy world is gnawing away at our mental health -- even costing lives. He lays out an 8-step plan to soften this sonic assault (starting with those cheap earbuds) and restore our relationship with sound.
The Hindus say, "Nada brahma," one translation of which is, "The world is sound." And, in a way, that's true, because everything is vibrating. In fact, all of you as you sit here right now are vibrating. Every part of your body is vibrating at different frequencies. So you are, in fact, a chord, each of you an individual chord. One definition of health may be that that chord is in complete harmony. Your ears can't hear that chord. They can actually hear amazing things. Your ears can hear 10 octaves. Incidentally, we see just one octave. Your ears are always on. You have no earlids. They work even when you sleep. The smallest sound you can perceive moves your eardrum just four atomic diameters. The loudest sound you can hear is a trillion times more powerful than that.
Ears are made not for hearing, but for listening. Listening is an active skill. Whereas hearing is passive, listening is something that we have to work at. It's a relationship with sound. And yet it's a skill that none of us are taught. For example, have you ever considered that there are listening positions, places you can listen from? Here are two of them. Reductive listening is listening "for." It reduces everything down to what's relevant, and it discards everything that's not relevant. Men typically listen reductively. So he's saying, "I've got this problem." He's saying, "Here's your solution. Thanks very much. Next." That's the way we talk, right guys?
Expansive listening, on the other hand, is listening "with," not listening "for." It's got no destination in mind. It's just enjoying the journey. Women typically listen expansively. If you look at these two, eye contact, facing each other, possibly both talking at the same time. (Laughter) Men, if you get nothing else out of this talk, practice expansive listening, and you can transform your relationships.
The trouble with listening is that so much of what we hear is noise, surrounding us all the time. Noise like this, according to the European Union, is reducing the health and the quality of life of 25 percent of the population of Europe. Two percent of the population of Europe -- that's 16 million people -- are having their sleep devastated by noise like that. Noise kills 200,000 people a year in Europe. It's a really big problem.
Now, when you were little, if you had noise, and you didn't want to hear it, you'd stick your fingers in your ears and hum. These days, you can do a similar thing, it just looks a bit cooler. It looks a bit like this. The trouble with widespread headphone use is it brings three really big health issues. The first really big health issue is a word that Murray Schafer coined: "schizophonia." It's a dislocation between what you see and what you hear. So, we're inviting into our lives the voices of people who are not present with us. I think there's something deeply unhealthy about living all the time in schizophonia.
The second problem that comes with headphone abuse is compression. We squash music to fit it into our pocket. and there is a cost attached to this. Listen to this. This is an uncompressed piece of music. (Music) And now the same piece of music with 98 percent of the data removed. (Music) I do hope that some of you at least can hear the difference between those two. There is a cost of compression. It makes you tired and irritable to have to make up all of that data. You're having to imagine it. It's not good for you in the long run.
The third problem with headphones is this: deafness -- noise-induced hearing disorder. 10 million Americans already have this for one reason or another, but really worryingly, 16 percent, roughly one in six, of American teenagers suffer from noise-induced hearing disorder as a result of headphone abuse. One study at an American university found that 61 percent of college freshmen had damaged hearing as a result of headphone abuse. We may be raising an entire generation of deaf people. Now that's a really serious problem.
I'll give you three quick tips to protect your ears, and pass these on to your children, please. professional hearing protectors are great; I use them all the time. If you're going to use headphones, buy the best ones you can afford, because quality means you don't have to have it so loud. If you can't hear somebody talking to you in a loud voice, it's too loud. And thirdly, if you're in bad sound, it's fine to put your fingers in your ears or just move away from it. Protect you ears in that way.
Let's move away from bad sound and look at some friends that I urge you to seek out. WWB: Wind, water, birds -- stochastic natural sounds composed of lots of individual random events, all of it very healthy, all of it sound that we evolved to over the years. Seek those sounds out; they're good for you, and so it this. Silence is beautiful. The Elizabethans described language as decorated silence. I urge you to move away from silence with intention and to design soundscapes just like works of art. Have a foreground, a background, all in beautiful proportion. It's fun to get into designing with sound. If you can't do it yourself, get a professional to do it for you. Sound design is the future, and I think it's the way we're going to change the way the world sounds.
I'm going to just run quickly through eight modalities, eight ways sound can improve health. First, ultrasound: we're very familiar with it from physical therapy. It's also now being used to treat cancer. Lithotripsy -- saving thousands of people a year from the scalpel by pulverizing stones with high-intensity sound. Sound healing is a wonderful modality. It's been around for thousands of years. I do urge you to explore this. There are great things being done there, treating now autism, dementia and other conditions. And music, of course. Just listening to music is good for you, if it's music that's made with good intention, made with love, generally. Devotional music, good. Mozart, good. There are all sorts of types of music that are very healthy.
And four modalities where you need to take some action and get involved. First of all, listen consciously. I hope that that after this talk you'll be doing that. It's a whole new dimension to your life, and it's wonderful to have that dimension. Secondly, get in touch with making some sound. Create sound. The voice is the instrument we all play, and yet how many of us are trained in using our voice? Get trained. Learn to sing. Learn to play an instrument. Musicians have bigger brains -- it's true. You can do this is groups as well. It's a fantastic antidote to schizophonia, to make music and sound in a group of people, whichever style you enjoy particularly. And let's take a stewarding role for the sound around us. Protect your ears? Yes, absolutely. Design soundscapes to be beautiful around you at home and at work. And let's start to speak up when people are assailing us with the noise that I played you early on.
So I'm going to leave you with seven things you can do right now to improve your health with sound. My vision is of a world that sounds beautiful, and if we all start doing these things, we will take a very big step in that direction. So I urge you to take that path.
I'm leaving you with a little more birdsong, which is very good for you. I wish you sound health.
(Applause)
Julian Treasure says our increasingly noisy world is gnawing away at our mental health -- even costing lives. He lays out an 8-step plan to soften this sonic assault (starting with those cheap earbuds) and restore our relationship with sound.
The Hindus say, "Nada brahma," one translation of which is, "The world is sound." And, in a way, that's true, because everything is vibrating. In fact, all of you as you sit here right now are vibrating. Every part of your body is vibrating at different frequencies. So you are, in fact, a chord, each of you an individual chord. One definition of health may be that that chord is in complete harmony. Your ears can't hear that chord. They can actually hear amazing things. Your ears can hear 10 octaves. Incidentally, we see just one octave. Your ears are always on. You have no earlids. They work even when you sleep. The smallest sound you can perceive moves your eardrum just four atomic diameters. The loudest sound you can hear is a trillion times more powerful than that.
Ears are made not for hearing, but for listening. Listening is an active skill. Whereas hearing is passive, listening is something that we have to work at. It's a relationship with sound. And yet it's a skill that none of us are taught. For example, have you ever considered that there are listening positions, places you can listen from? Here are two of them. Reductive listening is listening "for." It reduces everything down to what's relevant, and it discards everything that's not relevant. Men typically listen reductively. So he's saying, "I've got this problem." He's saying, "Here's your solution. Thanks very much. Next." That's the way we talk, right guys?
Expansive listening, on the other hand, is listening "with," not listening "for." It's got no destination in mind. It's just enjoying the journey. Women typically listen expansively. If you look at these two, eye contact, facing each other, possibly both talking at the same time. (Laughter) Men, if you get nothing else out of this talk, practice expansive listening, and you can transform your relationships.
The trouble with listening is that so much of what we hear is noise, surrounding us all the time. Noise like this, according to the European Union, is reducing the health and the quality of life of 25 percent of the population of Europe. Two percent of the population of Europe -- that's 16 million people -- are having their sleep devastated by noise like that. Noise kills 200,000 people a year in Europe. It's a really big problem.
Now, when you were little, if you had noise, and you didn't want to hear it, you'd stick your fingers in your ears and hum. These days, you can do a similar thing, it just looks a bit cooler. It looks a bit like this. The trouble with widespread headphone use is it brings three really big health issues. The first really big health issue is a word that Murray Schafer coined: "schizophonia." It's a dislocation between what you see and what you hear. So, we're inviting into our lives the voices of people who are not present with us. I think there's something deeply unhealthy about living all the time in schizophonia.
The second problem that comes with headphone abuse is compression. We squash music to fit it into our pocket. and there is a cost attached to this. Listen to this. This is an uncompressed piece of music. (Music) And now the same piece of music with 98 percent of the data removed. (Music) I do hope that some of you at least can hear the difference between those two. There is a cost of compression. It makes you tired and irritable to have to make up all of that data. You're having to imagine it. It's not good for you in the long run.
The third problem with headphones is this: deafness -- noise-induced hearing disorder. 10 million Americans already have this for one reason or another, but really worryingly, 16 percent, roughly one in six, of American teenagers suffer from noise-induced hearing disorder as a result of headphone abuse. One study at an American university found that 61 percent of college freshmen had damaged hearing as a result of headphone abuse. We may be raising an entire generation of deaf people. Now that's a really serious problem.
I'll give you three quick tips to protect your ears, and pass these on to your children, please. professional hearing protectors are great; I use them all the time. If you're going to use headphones, buy the best ones you can afford, because quality means you don't have to have it so loud. If you can't hear somebody talking to you in a loud voice, it's too loud. And thirdly, if you're in bad sound, it's fine to put your fingers in your ears or just move away from it. Protect you ears in that way.
Let's move away from bad sound and look at some friends that I urge you to seek out. WWB: Wind, water, birds -- stochastic natural sounds composed of lots of individual random events, all of it very healthy, all of it sound that we evolved to over the years. Seek those sounds out; they're good for you, and so it this. Silence is beautiful. The Elizabethans described language as decorated silence. I urge you to move away from silence with intention and to design soundscapes just like works of art. Have a foreground, a background, all in beautiful proportion. It's fun to get into designing with sound. If you can't do it yourself, get a professional to do it for you. Sound design is the future, and I think it's the way we're going to change the way the world sounds.
I'm going to just run quickly through eight modalities, eight ways sound can improve health. First, ultrasound: we're very familiar with it from physical therapy. It's also now being used to treat cancer. Lithotripsy -- saving thousands of people a year from the scalpel by pulverizing stones with high-intensity sound. Sound healing is a wonderful modality. It's been around for thousands of years. I do urge you to explore this. There are great things being done there, treating now autism, dementia and other conditions. And music, of course. Just listening to music is good for you, if it's music that's made with good intention, made with love, generally. Devotional music, good. Mozart, good. There are all sorts of types of music that are very healthy.
And four modalities where you need to take some action and get involved. First of all, listen consciously. I hope that that after this talk you'll be doing that. It's a whole new dimension to your life, and it's wonderful to have that dimension. Secondly, get in touch with making some sound. Create sound. The voice is the instrument we all play, and yet how many of us are trained in using our voice? Get trained. Learn to sing. Learn to play an instrument. Musicians have bigger brains -- it's true. You can do this is groups as well. It's a fantastic antidote to schizophonia, to make music and sound in a group of people, whichever style you enjoy particularly. And let's take a stewarding role for the sound around us. Protect your ears? Yes, absolutely. Design soundscapes to be beautiful around you at home and at work. And let's start to speak up when people are assailing us with the noise that I played you early on.
So I'm going to leave you with seven things you can do right now to improve your health with sound. My vision is of a world that sounds beautiful, and if we all start doing these things, we will take a very big step in that direction. So I urge you to take that path.
I'm leaving you with a little more birdsong, which is very good for you. I wish you sound health.
(Applause)
TALKS - Sebastian Seung: I am my connectome
About this talk
Sebastian Seung is mapping a massively ambitious new model of the brain that focuses on the connections between each neuron. He calls it our "connectome," and it's as individual as our genome -- and understanding it could open a new way to understand our brains and our minds.
We live in in a remarkable time, the age of genomics. Your genome is the entire sequence of your DNA. Your sequence and mine are slightly different. That's why we look different. I've got brown eyes. You might have blue or gray. But it's not just skin-deep. The headlines tell us that genes can give us scary diseases, maybe even shape our personality, or give us mental disorders. Our genes seem to have awesome power over our destinies. And yet, I would like to think that I am more than my genes. What do you guys think? Are you more than your genes? (Audience: Yes.) Yes? I think some people agree with me. I think we should make a statement. I think we should say it all together. All right: "I'm more than my genes" -- all together. Everybody: I am more than my genes. (Cheering) Sebastian Seung: What am I? (Laughter) I am my connectome. Now, since you guys are really great, maybe you can humor me and say this all together too. (Laughter) Right. All together now. Everybody: I am my connectome. SS: That sounded great. You know, you guys are so great, you don't even know what a connectome is, and you're willing to play along with me. I could just go home now.
Well, so far only one connectome is known, that of this tiny worm. Its modest nervous system consists of just 300 neurons. And in the 1970s and '80s, a team of scientists mapped all 7,000 connections between the neurons. In this diagram, every node is a neuron, and every line is a connection. This is the connectome of the worm C. elegans. Your connectome is far more complex than this, because your brain contains 100 billion neurons and 10,000 times as many connections. There's a diagram like this for your brain, but there's no way it would fit on this slide. Your connectome contains one million times more connections than your genome has letters. That's a lot of information.
What's in that information? We don't know for sure, but there are theories. Since the 19th century, neuroscientists have speculated that maybe your memories -- the information that makes you you -- maybe your memories are stored in the connections between your brain's neurons. And perhaps other aspects of your personal identity -- maybe your personality and your intellect -- maybe they're also encoded in the connections between your neurons. And so now you can see why I proposed this hypothesis: I am my connectome. I didn't ask you to chant it because it's true, I just want you to remember it. And in fact, we don't know if this hypothesis is correct, because we have never had technologies powerful enough to test it. Finding that worm connectome took over a dozen years of tedious labor. And to find the connectomes of brains more like our own, we need more sophisticated technologies, that are automated, that will speed up the process of finding connectomes. And in the next few minutes, I'll tell you about some of these technologies, which are currently under development in my lab and the labs of my collaborators.
Now you've probably seen pictures of neurons before. You can recognize them instantly by their fantastic shapes. They extend long and delicate branches, and in short, they look like trees. But this is just a single neuron. In order to find connectomes, we have to see all the neurons at the same time. So let's meet Bobby Kasthuri who works in the laboratory of Jeff Lichtman at Harvard University. Bobby is holding fantastically thin slices of a mouse brain. And we're zooming in by a factor of 100,000 times to obtain the resolution, so that we can see the branches of neurons all at the same time. Except, you still may not really recognize them, and that's because we have to work in three dimensions.
If we take many images of many slices of the brain and stack them up, we get a three-dimensional image. And still, you may not see the branches. So we start at the top, and we color in the cross-section of one branch in red, And we do that for the next slice and for the next slice. And we keep on doing that, slice after slice. If we continue through the entire stack, we can reconstruct the three-dimensional shape of a small fragment of a branch of a neuron. And we can do that for another neuron in green. And you can see that the green neuron touches the red neuron at two locations, and these are what are called synapses.
Let's zoom in on one synapse. And keep your eyes on the interior of the green neuron. You should see small circles. These are called vesicles. They contain a molecule know as a neurotransmitter. And so when the green neuron wants to communicate, it wants to send a message to the red neuron, it spits out neurotransmitter. At the synapse, the two neurons are said to be connected like two friends talking on the telephone.
So you see how to find a synapse. How can we find an entire connectome? Well, we take this three-dimensional stack of images and treat it as a gigantic three-dimensional coloring book. We color every neuron in in a different color, and then we look through all of the images, find the synapses and note the colors of the two neurons involved in each synapse. If we can do that throughout all the images, we could find a connectome.
Now, at this point, you've learned the basics of neurons and synapses. And so I think we're ready to tackle one of the most important questions in neuroscience: how are the brains of men and women different? (Laughter) According to this self-help book, guys brains are like waffles; they keep their lives compartmentalized in boxes. Girls brains are like spaghetti; everything in their life is connected to everything else. (Laughter) You guys are laughing, but, you know, this book changed my life. (Laughter) But seriously, what's wrong with this? You already know enough to tell me. What's wrong with this statement? It doesn't matter whether you're a guy or girl, everyone's brains are like spaghetti. Or maybe really, really fine capellini with branches. Just as one strand of spaghetti contacts many other strands on your plate, one neuron touches many other neurons through their entangled branches. One neuron can be connected to so many other neurons, because there can be synapses at these points of contact. By now, you might have sort of lost perspective on how large this cube of brain tissue actually is.
And so let's do a series of comparisons to show you. I'll show you. This is very tiny. It's just six microns on a side. So, here's how it stacks up against an entire neuron. And you can tell that, really, only the smallest fragments of branches are contained inside this cube. And a neuron, well, that's smaller than brain. And that's just a mouse brain. It's a lot smaller than a human brain. So when show my friends this, sometimes they've told me, "You know, Sebastian, you should just give up. Neuroscience is hopeless." Because if you look at a brain with your naked eye, you don't really see how complex it is, but when you use a microscope, finally, the hidden complexity is revealed.
In the 17th century, the mathematician and philosopher, Blaise Pascal, wrote of his dread of the infinite, his feeling of insignificance at contemplating the vast reaches of outer space. And, as a scientist, I'm not supposed to talk about my feelings. Too much information, professor. (Laughter) But may I? (Laughter) (Applause) I feel curiosity, and I feel wonder, but at times I have also felt despair. Why did I choose to study this organ that is so awesome in its complexity that it might well be infinite? It's absurd. How could we even dare to think that we might ever understand this?
And yet, I persist in this quixotic endeavor. And indeed, these days I harbor new hopes. Some day, a fleet of microscopes will capture every neuron and every synapse in a vast database of images. And some day, artificially intelligent supercomputers will analyze the images without human assistance to summarize them in a connectome. I do not know, but I hope that I will live to see that day. Because finding an entire human connectome is one of the greatest technological challenges of all time. It will take the work of generations to succeed. At the present time, my collaborators and I, what we're aiming for is much more modest -- just to find partial connectomes of tiny chunks of mouse and human brain. But even that will be enough for the first tests of this hypothesis that I am my connectome. For now, let me try to convince you of the plausibility of this hypothesis, that it's actually worth taking seriously.
As you grow during childhood and age during adulthood, your personal identity changes slowly. Likewise, every connectome changes over time. What kinds of changes happen? Well, neurons, like trees, can grow new branches, and they can lose old ones. Synapses can be created, and they can be eliminated. And synapses can grow larger, and they can grow smaller. Second question: what causes these changes? Well, it's true. To some extent, they are programmed by your genes. But that's not the whole story, because there are signals, electrical signals, that travel along the branches of neurons and chemical signals that jump across from branch to branch. These signals are called neural activity. And there's a lot of evidence that neural activity is encoding our thoughts, feelings and perceptions, our mental experiences. And there's a lot of evidence that neural activity can cause your connections to change. And if you put those two facts together, it means that your experiences can change your connectome. And that's why every connectome is unique, even those of genetically identical twins. The connectome is where nature meets nurture. And it might true that just the mere act of thinking can change your connectome -- an idea that you may find empowering.
What's in this picture? A cool and refreshing stream of water, you say. What else is in this picture? Do not forget that groove in the Earth called the stream bed. Without it, the water would not know in which direction to flow. And with the stream, I would like to propose a metaphor for the relationship between neural activity and connectivity. Neural activity is constantly changing. It's like the water of the stream; it never sits still. The connections of the brain's neural network determines the pathways along which neural activity flows. And so the connectome is like bed of the stream. But the metaphor is richer than that. Because it's true that the stream bed guides the flow of the water, but over long timescales, the water also reshapes the bed of the stream. And as I told you just now, neural activity can change the connectome. And if you'll allow me to ascend to metaphorical heights, I will remind you that neural activity is the physical basis -- or so neuroscientists think -- of thoughts, feelings and perceptions. And so we might even speak of the stream of consciousness. Neural activity is its water, and the connectome is its bed.
So let's return from the heights of metaphor and return to science. Suppose our technologies for finding connectomes actually work. How will we go about testing the hypothesis "I am my connectome"? Well, I propose a direct test. Let us attempt to read out memories from connectomes. Consider the memory of long temporal sequences of movements, like a pianist playing a Beethoven sonata. According to a theory that dates back to the 19th century, such memories are stored as chains of synaptic connections inside your brain. Because, if the first neurons in the chain are activated, through their synapses they send messages to the second neurons, which are activated, and so on down the line, like a chain of falling dominoes. And this sequence of neural activation is hypothesized to be the neural basis of those sequence of movements.
So one way of trying to test the theory is to look for such chains inside connectomes. But it won't be easy, because they're not going to look like this. They're going to be scrambled up. So we'll have to use our computers to try to unscramble the chain. And if we can do that, the sequence of the neurons we recover from that unscrambling will be a prediction of the pattern of neural activity that is replayed in the brain during memory recall. And if that were successful, that would be the first example of reading a memory from a connectome.
(Laughter)
What a mess. Have you ever tried to wire up a system as complex as this? I hope not. But if you have, you know it's very easy to make a mistake. The branches of neurons are like the wires of the brain. Can anyone guess: what's the total length of wires in your brain? I'll give you a hint. It's a big number. (Laughter) I estimate, millions of miles. All packed in your skull. And if you appreciate that number, you can easily see there is huge potential for mis-wiring of the brain. And indeed, the popular press loves headlines like, "Anorexic brains are wired differently," or, "Autistic brains are wired differently." These are plausible claims, but in truth, we can't see the brain's wiring clearly enough to tell if these are really true. And so the technologies for seeing connectomes will allow us to finally read mis-wiring of the brain, to see mental disorders in connectomes.
Sometimes the best way to test a hypothesis is to consider its most extreme implication. Philosophers know this game very well. If you believe that I am my connectome, I think you must also accept the idea that death is the destruction of your connectome. I mention this because there are prophets today who claim that technology will fundamentally alter the human condition and perhaps even transform the human species. One of their most cherished dreams is to cheat death by that practice known as cryonics. If you pay 100,000 dollars, you can arrange to have your body frozen after death and stored in liquid nitrogen in one of these tanks in an Arizona warehouse, awaiting a future civilization that is advanced to resurrect you.
Should we ridicule the modern seekers of immortality, calling them fools? Or will they some day chuckle over our graves? I don't know. I prefer to test their beliefs, scientifically. I propose that we attempt to find a connectome of a frozen brain. We know that damage to the brain occurs after death and during freezing. The question is: has that damage erased the connectome? If it has, there is no way that any future civilization will be able to recover the memories of these frozen brains. Resurrection might succeed for the body, but not for the mind. On the other hand, if the connectome is still intact, we cannot ridicule the claims of cryonics so easily.
I've described a quest that begins in the world of the very small, and propels us to the world of the far future. Connectomes will mark a turning point in human history. As we evolved from our ape-like ancestors on the African savanna, what distinguished us was our larger brains. We have used our brains to fashion ever more amazing technologies. Eventually, these technologies will become so powerful that we will use them to know ourselves by deconstructing and reconstructing our own brains. I believe that this voyage of self-discovery is not just for scientists, but for all of us. And I'm grateful for the opportunity to share this voyage with you today.
Thank you.
(Applause)
Sebastian Seung is mapping a massively ambitious new model of the brain that focuses on the connections between each neuron. He calls it our "connectome," and it's as individual as our genome -- and understanding it could open a new way to understand our brains and our minds.
We live in in a remarkable time, the age of genomics. Your genome is the entire sequence of your DNA. Your sequence and mine are slightly different. That's why we look different. I've got brown eyes. You might have blue or gray. But it's not just skin-deep. The headlines tell us that genes can give us scary diseases, maybe even shape our personality, or give us mental disorders. Our genes seem to have awesome power over our destinies. And yet, I would like to think that I am more than my genes. What do you guys think? Are you more than your genes? (Audience: Yes.) Yes? I think some people agree with me. I think we should make a statement. I think we should say it all together. All right: "I'm more than my genes" -- all together. Everybody: I am more than my genes. (Cheering) Sebastian Seung: What am I? (Laughter) I am my connectome. Now, since you guys are really great, maybe you can humor me and say this all together too. (Laughter) Right. All together now. Everybody: I am my connectome. SS: That sounded great. You know, you guys are so great, you don't even know what a connectome is, and you're willing to play along with me. I could just go home now.
Well, so far only one connectome is known, that of this tiny worm. Its modest nervous system consists of just 300 neurons. And in the 1970s and '80s, a team of scientists mapped all 7,000 connections between the neurons. In this diagram, every node is a neuron, and every line is a connection. This is the connectome of the worm C. elegans. Your connectome is far more complex than this, because your brain contains 100 billion neurons and 10,000 times as many connections. There's a diagram like this for your brain, but there's no way it would fit on this slide. Your connectome contains one million times more connections than your genome has letters. That's a lot of information.
What's in that information? We don't know for sure, but there are theories. Since the 19th century, neuroscientists have speculated that maybe your memories -- the information that makes you you -- maybe your memories are stored in the connections between your brain's neurons. And perhaps other aspects of your personal identity -- maybe your personality and your intellect -- maybe they're also encoded in the connections between your neurons. And so now you can see why I proposed this hypothesis: I am my connectome. I didn't ask you to chant it because it's true, I just want you to remember it. And in fact, we don't know if this hypothesis is correct, because we have never had technologies powerful enough to test it. Finding that worm connectome took over a dozen years of tedious labor. And to find the connectomes of brains more like our own, we need more sophisticated technologies, that are automated, that will speed up the process of finding connectomes. And in the next few minutes, I'll tell you about some of these technologies, which are currently under development in my lab and the labs of my collaborators.
Now you've probably seen pictures of neurons before. You can recognize them instantly by their fantastic shapes. They extend long and delicate branches, and in short, they look like trees. But this is just a single neuron. In order to find connectomes, we have to see all the neurons at the same time. So let's meet Bobby Kasthuri who works in the laboratory of Jeff Lichtman at Harvard University. Bobby is holding fantastically thin slices of a mouse brain. And we're zooming in by a factor of 100,000 times to obtain the resolution, so that we can see the branches of neurons all at the same time. Except, you still may not really recognize them, and that's because we have to work in three dimensions.
If we take many images of many slices of the brain and stack them up, we get a three-dimensional image. And still, you may not see the branches. So we start at the top, and we color in the cross-section of one branch in red, And we do that for the next slice and for the next slice. And we keep on doing that, slice after slice. If we continue through the entire stack, we can reconstruct the three-dimensional shape of a small fragment of a branch of a neuron. And we can do that for another neuron in green. And you can see that the green neuron touches the red neuron at two locations, and these are what are called synapses.
Let's zoom in on one synapse. And keep your eyes on the interior of the green neuron. You should see small circles. These are called vesicles. They contain a molecule know as a neurotransmitter. And so when the green neuron wants to communicate, it wants to send a message to the red neuron, it spits out neurotransmitter. At the synapse, the two neurons are said to be connected like two friends talking on the telephone.
So you see how to find a synapse. How can we find an entire connectome? Well, we take this three-dimensional stack of images and treat it as a gigantic three-dimensional coloring book. We color every neuron in in a different color, and then we look through all of the images, find the synapses and note the colors of the two neurons involved in each synapse. If we can do that throughout all the images, we could find a connectome.
Now, at this point, you've learned the basics of neurons and synapses. And so I think we're ready to tackle one of the most important questions in neuroscience: how are the brains of men and women different? (Laughter) According to this self-help book, guys brains are like waffles; they keep their lives compartmentalized in boxes. Girls brains are like spaghetti; everything in their life is connected to everything else. (Laughter) You guys are laughing, but, you know, this book changed my life. (Laughter) But seriously, what's wrong with this? You already know enough to tell me. What's wrong with this statement? It doesn't matter whether you're a guy or girl, everyone's brains are like spaghetti. Or maybe really, really fine capellini with branches. Just as one strand of spaghetti contacts many other strands on your plate, one neuron touches many other neurons through their entangled branches. One neuron can be connected to so many other neurons, because there can be synapses at these points of contact. By now, you might have sort of lost perspective on how large this cube of brain tissue actually is.
And so let's do a series of comparisons to show you. I'll show you. This is very tiny. It's just six microns on a side. So, here's how it stacks up against an entire neuron. And you can tell that, really, only the smallest fragments of branches are contained inside this cube. And a neuron, well, that's smaller than brain. And that's just a mouse brain. It's a lot smaller than a human brain. So when show my friends this, sometimes they've told me, "You know, Sebastian, you should just give up. Neuroscience is hopeless." Because if you look at a brain with your naked eye, you don't really see how complex it is, but when you use a microscope, finally, the hidden complexity is revealed.
In the 17th century, the mathematician and philosopher, Blaise Pascal, wrote of his dread of the infinite, his feeling of insignificance at contemplating the vast reaches of outer space. And, as a scientist, I'm not supposed to talk about my feelings. Too much information, professor. (Laughter) But may I? (Laughter) (Applause) I feel curiosity, and I feel wonder, but at times I have also felt despair. Why did I choose to study this organ that is so awesome in its complexity that it might well be infinite? It's absurd. How could we even dare to think that we might ever understand this?
And yet, I persist in this quixotic endeavor. And indeed, these days I harbor new hopes. Some day, a fleet of microscopes will capture every neuron and every synapse in a vast database of images. And some day, artificially intelligent supercomputers will analyze the images without human assistance to summarize them in a connectome. I do not know, but I hope that I will live to see that day. Because finding an entire human connectome is one of the greatest technological challenges of all time. It will take the work of generations to succeed. At the present time, my collaborators and I, what we're aiming for is much more modest -- just to find partial connectomes of tiny chunks of mouse and human brain. But even that will be enough for the first tests of this hypothesis that I am my connectome. For now, let me try to convince you of the plausibility of this hypothesis, that it's actually worth taking seriously.
As you grow during childhood and age during adulthood, your personal identity changes slowly. Likewise, every connectome changes over time. What kinds of changes happen? Well, neurons, like trees, can grow new branches, and they can lose old ones. Synapses can be created, and they can be eliminated. And synapses can grow larger, and they can grow smaller. Second question: what causes these changes? Well, it's true. To some extent, they are programmed by your genes. But that's not the whole story, because there are signals, electrical signals, that travel along the branches of neurons and chemical signals that jump across from branch to branch. These signals are called neural activity. And there's a lot of evidence that neural activity is encoding our thoughts, feelings and perceptions, our mental experiences. And there's a lot of evidence that neural activity can cause your connections to change. And if you put those two facts together, it means that your experiences can change your connectome. And that's why every connectome is unique, even those of genetically identical twins. The connectome is where nature meets nurture. And it might true that just the mere act of thinking can change your connectome -- an idea that you may find empowering.
What's in this picture? A cool and refreshing stream of water, you say. What else is in this picture? Do not forget that groove in the Earth called the stream bed. Without it, the water would not know in which direction to flow. And with the stream, I would like to propose a metaphor for the relationship between neural activity and connectivity. Neural activity is constantly changing. It's like the water of the stream; it never sits still. The connections of the brain's neural network determines the pathways along which neural activity flows. And so the connectome is like bed of the stream. But the metaphor is richer than that. Because it's true that the stream bed guides the flow of the water, but over long timescales, the water also reshapes the bed of the stream. And as I told you just now, neural activity can change the connectome. And if you'll allow me to ascend to metaphorical heights, I will remind you that neural activity is the physical basis -- or so neuroscientists think -- of thoughts, feelings and perceptions. And so we might even speak of the stream of consciousness. Neural activity is its water, and the connectome is its bed.
So let's return from the heights of metaphor and return to science. Suppose our technologies for finding connectomes actually work. How will we go about testing the hypothesis "I am my connectome"? Well, I propose a direct test. Let us attempt to read out memories from connectomes. Consider the memory of long temporal sequences of movements, like a pianist playing a Beethoven sonata. According to a theory that dates back to the 19th century, such memories are stored as chains of synaptic connections inside your brain. Because, if the first neurons in the chain are activated, through their synapses they send messages to the second neurons, which are activated, and so on down the line, like a chain of falling dominoes. And this sequence of neural activation is hypothesized to be the neural basis of those sequence of movements.
So one way of trying to test the theory is to look for such chains inside connectomes. But it won't be easy, because they're not going to look like this. They're going to be scrambled up. So we'll have to use our computers to try to unscramble the chain. And if we can do that, the sequence of the neurons we recover from that unscrambling will be a prediction of the pattern of neural activity that is replayed in the brain during memory recall. And if that were successful, that would be the first example of reading a memory from a connectome.
(Laughter)
What a mess. Have you ever tried to wire up a system as complex as this? I hope not. But if you have, you know it's very easy to make a mistake. The branches of neurons are like the wires of the brain. Can anyone guess: what's the total length of wires in your brain? I'll give you a hint. It's a big number. (Laughter) I estimate, millions of miles. All packed in your skull. And if you appreciate that number, you can easily see there is huge potential for mis-wiring of the brain. And indeed, the popular press loves headlines like, "Anorexic brains are wired differently," or, "Autistic brains are wired differently." These are plausible claims, but in truth, we can't see the brain's wiring clearly enough to tell if these are really true. And so the technologies for seeing connectomes will allow us to finally read mis-wiring of the brain, to see mental disorders in connectomes.
Sometimes the best way to test a hypothesis is to consider its most extreme implication. Philosophers know this game very well. If you believe that I am my connectome, I think you must also accept the idea that death is the destruction of your connectome. I mention this because there are prophets today who claim that technology will fundamentally alter the human condition and perhaps even transform the human species. One of their most cherished dreams is to cheat death by that practice known as cryonics. If you pay 100,000 dollars, you can arrange to have your body frozen after death and stored in liquid nitrogen in one of these tanks in an Arizona warehouse, awaiting a future civilization that is advanced to resurrect you.
Should we ridicule the modern seekers of immortality, calling them fools? Or will they some day chuckle over our graves? I don't know. I prefer to test their beliefs, scientifically. I propose that we attempt to find a connectome of a frozen brain. We know that damage to the brain occurs after death and during freezing. The question is: has that damage erased the connectome? If it has, there is no way that any future civilization will be able to recover the memories of these frozen brains. Resurrection might succeed for the body, but not for the mind. On the other hand, if the connectome is still intact, we cannot ridicule the claims of cryonics so easily.
I've described a quest that begins in the world of the very small, and propels us to the world of the far future. Connectomes will mark a turning point in human history. As we evolved from our ape-like ancestors on the African savanna, what distinguished us was our larger brains. We have used our brains to fashion ever more amazing technologies. Eventually, these technologies will become so powerful that we will use them to know ourselves by deconstructing and reconstructing our own brains. I believe that this voyage of self-discovery is not just for scientists, but for all of us. And I'm grateful for the opportunity to share this voyage with you today.
Thank you.
(Applause)
Gary Wolf: The quantified self
About this talk
At TED@Cannes, Gary Wolf gives a 5-min intro to an intriguing new pastime: using mobile apps and always-on gadgets to track and analyze your body, mood, diet, spending -- just about everything in daily life you can measure -- in gloriously geeky detail.
I got up this morning at 6:10am after going to sleep at 12:45am. I was awakened once during the night. My heart rate was 61 beats per minute. My blood pressure, 127 over 74. I had zero minutes of exercise yesterday, so my maximum heart rate during exercise wasn't calculated. I had about 600 milligrams of caffeine, zero of alcohol. And my score on the Narcissism Personality Index, or the NPI-16, is a reassuring 0.31.
We know that numbers are useful for us when we advertise, manage, govern, search. I'm going to talk about how they're useful when we reflect, learn, remember, and want to improve. A few year ago, Kevin Kelly, my partner, and I noticed that people were subjecting themselves to regimes of quantitative measurement and self-tracking that went far beyond the ordinary, familiar habits such as stepping on a scale every day. People were tracking their food via Twitter, their kids' diapers on their iPhone. They were making detailed journals of their spending, their mood, their symptoms, their treatments.
Now, we know some of the technological facts that are driving this change in our lifestyle -- the uptake and diffusion of mobile devices, the exponential improvement in data storage and data processing, and the remarkable improvement in human biometric sensors. This little black dot there is a 3D accelerometer. It tracks your movement through space. It is, as you can see, very small and also very cheap. They're now down to well under a dollar a piece, and they're going into all kinds of devices. But what's interesting is the incredible detailed information that you can get from just one sensor like this. This kind of sensor is in the hit biometric device -- among early adopters at the moment -- the Fitbit. This tracks your activity and also your sleep. It has just that sensor in it.
You're probably familiar with the Nike+ system. I just put it up because that little blue dot is the sensor. It's really just a pressure sensor like the kind that's in a doorbell. And Nike knows how to get your pace and and distance from just that sensor. This is the strap that people use to transmit heart-rate data to their Nike+ system.
This is a beautiful, new device that gives you detailed sleep tracking data, not just whether you're asleep or awake, but also your phase of sleep -- deep sleep, light sleep, REM sleep. The sensor is just a little strip of metal in that headband there. The rest of it is the bedside console. Just for reference, this is a sleep tracking system from just a few years ago -- I mean, really until now. And this is the sleep tracking system of today.
This just was presented at a health care conference in D.C. Most of what you see there is an asthma inhaler, but the top is a very small GPS transceiver, which gives you the date and location of an asthma incident, giving you a new awareness of your vulnerability in relation to time and environmental factors.
Now, we know that new tools are changing our sense of self in the world -- these tiny sensors that gather data in nature, the ubiquitous computing that allows that data to be understood and used, and of course the social networks that allow people to collaborate and contribute. But we think of these tools as pointing outward, as windows, and I'd just like to invite you to think of them as also turning inward and becoming mirrors. So when we think about using them to get some systematic improvement, we also think about how they can be useful for self-improvement, for self-discovery, self-awareness, self-knowledge.
Here's a biometric device: a pair of Apple Earbuds. Last year, Apple filed some patents to get blood oxygenation, heart rate and body temperature via the Earbuds. What is this for? What should it be for? Some people will say it's for biometric security. Some people will say it's for public health research. Some people will say it's for avant-garde marketing research. I'd like to tell you that it's also for self-knowledge. And the self isn't the only thing; it's not even most things. The self is just our operation center, our consciousness, our moral compass. So, if we want to act more effectively in the world, we have to get to know ourselves better.
Thank you.
At TED@Cannes, Gary Wolf gives a 5-min intro to an intriguing new pastime: using mobile apps and always-on gadgets to track and analyze your body, mood, diet, spending -- just about everything in daily life you can measure -- in gloriously geeky detail.
I got up this morning at 6:10am after going to sleep at 12:45am. I was awakened once during the night. My heart rate was 61 beats per minute. My blood pressure, 127 over 74. I had zero minutes of exercise yesterday, so my maximum heart rate during exercise wasn't calculated. I had about 600 milligrams of caffeine, zero of alcohol. And my score on the Narcissism Personality Index, or the NPI-16, is a reassuring 0.31.
We know that numbers are useful for us when we advertise, manage, govern, search. I'm going to talk about how they're useful when we reflect, learn, remember, and want to improve. A few year ago, Kevin Kelly, my partner, and I noticed that people were subjecting themselves to regimes of quantitative measurement and self-tracking that went far beyond the ordinary, familiar habits such as stepping on a scale every day. People were tracking their food via Twitter, their kids' diapers on their iPhone. They were making detailed journals of their spending, their mood, their symptoms, their treatments.
Now, we know some of the technological facts that are driving this change in our lifestyle -- the uptake and diffusion of mobile devices, the exponential improvement in data storage and data processing, and the remarkable improvement in human biometric sensors. This little black dot there is a 3D accelerometer. It tracks your movement through space. It is, as you can see, very small and also very cheap. They're now down to well under a dollar a piece, and they're going into all kinds of devices. But what's interesting is the incredible detailed information that you can get from just one sensor like this. This kind of sensor is in the hit biometric device -- among early adopters at the moment -- the Fitbit. This tracks your activity and also your sleep. It has just that sensor in it.
You're probably familiar with the Nike+ system. I just put it up because that little blue dot is the sensor. It's really just a pressure sensor like the kind that's in a doorbell. And Nike knows how to get your pace and and distance from just that sensor. This is the strap that people use to transmit heart-rate data to their Nike+ system.
This is a beautiful, new device that gives you detailed sleep tracking data, not just whether you're asleep or awake, but also your phase of sleep -- deep sleep, light sleep, REM sleep. The sensor is just a little strip of metal in that headband there. The rest of it is the bedside console. Just for reference, this is a sleep tracking system from just a few years ago -- I mean, really until now. And this is the sleep tracking system of today.
This just was presented at a health care conference in D.C. Most of what you see there is an asthma inhaler, but the top is a very small GPS transceiver, which gives you the date and location of an asthma incident, giving you a new awareness of your vulnerability in relation to time and environmental factors.
Now, we know that new tools are changing our sense of self in the world -- these tiny sensors that gather data in nature, the ubiquitous computing that allows that data to be understood and used, and of course the social networks that allow people to collaborate and contribute. But we think of these tools as pointing outward, as windows, and I'd just like to invite you to think of them as also turning inward and becoming mirrors. So when we think about using them to get some systematic improvement, we also think about how they can be useful for self-improvement, for self-discovery, self-awareness, self-knowledge.
Here's a biometric device: a pair of Apple Earbuds. Last year, Apple filed some patents to get blood oxygenation, heart rate and body temperature via the Earbuds. What is this for? What should it be for? Some people will say it's for biometric security. Some people will say it's for public health research. Some people will say it's for avant-garde marketing research. I'd like to tell you that it's also for self-knowledge. And the self isn't the only thing; it's not even most things. The self is just our operation center, our consciousness, our moral compass. So, if we want to act more effectively in the world, we have to get to know ourselves better.
Thank you.
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